Just got feedback from RRS (look at the PS below):
HI Carlos, I doubt that plate for the D7 grip will work with that camera body, or BGE6 battery grip. In fact if it would have fit we would not have had to make two plates, so I can safely say it will not fit to our standards. You may try it and find that it will work for you in a pinch. Without those two cameras in my hand I can’t tell. The plate you are looking for is the BGE6-L (if you using the grip on that 5D MarkII) if you not using the grip the plate is the B5D2-L. With UPS World Wide Express I can have it to you just about anywhere in the world in 2-3 working days(yes by the weekend). Let me know what you decide. I am here to help you if I can. J Happy shooting!
PS, for renting a camera I have used lens foot plates to get the camera in the clamp. A lens foot plate such as an L84 (I see you have one) can be mounted on just about any camera in a fore aft orientation. That will allow you to mount that camera in the clamp. You will have to use the drop notch to go vertical, or shoot with a collared lens and let that camera hang off the back. Then you can spin the camera in the collared lens. I am here for you if you want to get the other plate. J Good Luck.
Thank you, Casey
Customer Support Representative for Really Right Stuff LLC
www.ReallyRightStuff.com
I had of course forgotten about the L84 plate! Aren't they simply amazing?